Aluminum bottle caps feature a simple appearance yet fine craftsmanship. Advanced printing technology ensures uniform color and exquisite patterns, providing consumers with an elegant visual experience. In addition, aluminum caps offer excellent sealing performance and can withstand high-temperature sterilization, making them widely used and highly functional.
How Are Aluminum Caps Manufactured?
1. Rolling and Cutting
Aluminum sheets are first rolled into thin strips with a thickness of approximately 0.2 to 0.5 mm, depending on the application requirements. These sheets are then cut into blanks of designated sizes and shapes using dies or high-speed cutting machines. A coating machine applies a bright-colored lacquer to the surface, followed by a 25-minute drying process. Then, a printing cylinder is used to imprint logos or patterns onto the aluminum sheet.
2. Embossing and Forming
The cut aluminum blanks pass through multiple dies and punches to gradually form the structural features of the bottle cap, such as threads, ribs, and flanges. This stage demands high-precision operations to ensure the caps perfectly match the container openings.
3. Annealing Treatment
Formed caps typically undergo annealing, where they are heated to a specific temperature and then slowly cooled. This process enhances the ductility and workability of the aluminum material while improving the cap's strength and durability.
4. Surface Treatment and Printing
According to branding needs, the cap surface can undergo hot stamping, screen printing, or pad printing to add logos, text, or images. The hot stamping process uses heated molds to transfer ink patterns onto the cap surface, offering excellent adhesion and visual appeal.
5. Cap Assembly
Automatic capping equipment is used to precisely install the aluminum cap onto the container opening. This process involves clamping, screwing, and applying torque to ensure a tight seal. Caps may be threaded, twist-off, or tamper-evident in design.
6. Quality Control
The final stage of production includes rigorous quality checks such as seal integrity testing, dimensional accuracy inspection, surface defect screening, and strength assessment to ensure each cap meets product specifications and industry standards.
7. Packaging and Shipping
Finished aluminum caps that pass inspection are packed and prepared for shipment to customers.
